Electrolytic signal recording



Nov. 9, 1948. c; J. YOUNG 2,453,434

ELECTROLYTIC smruu. RECORDING Filed lay 31, 1946 I 2 Shoots-Sheet. 1

a RECEIVER 24 INVENTOR CHARLES J. YOUNG Maw aw ATTORNEY Nov. 9, 1948. c. J. YOUNG I .4534

mac-momma. smum Raconnme Filed lay 31, 1946 '2 sham-sheet 2 INVENTOR $HARLES- J. YOUNG A'r'ToRNEY Patented Nov. 9, 1948 ELECTROLYTIC SIGNAL RECORDING Charles J. Young, Princeton, N. 1., asaignor to Radio Corporation of America, a corporation of Delaware Application May 31, 1040, Serial No. 673,225

4 Claims. (01. sis-'14) l The present invention relates to electrolytic recording and more particularly, although not necessarily exclusively, to the recording of electrical signals in the form of permanent marks on a record sheet so that the marks appear on a I permanent; background.

An important aspect of the invention resides in the provision of a record sheet conditioning means having combined functions. In accordance with the invention an electrically sensitive substance is applied-to a record sheet in any suitable manner. This substance is capable of producing marks in or upon the sheet upon application of electrical effects thereto. Premature or spon'- taneous production of undesired marks in the form of discoloration is prevented, preferably'by chemical means, prior to subjection of the record sheet to the recording process. Further undesired color change or undesired marking is prevented'following the recording process. Also, in

accordance with the invention, treatment of the record sheet to prevent further discoloration conclition-s the sheet for subsequent use as a permanent record resembling a sheet of ordinary printed matter or the like.

Accordingly, an important object of the inven- 'tion is to provide novel means for producing novel means for treating a record sheet toinsure' permanent contrast between electrically produced marks on the sheet and the unrecorded background thereof.

A further object is to provide a means for drying and smoothing 0r ironing a record sheet and at the same time conditioning the record sheet to prevent discoloration thereof. 1

A still further object is to provide a facsimile recorder having means for treating a record sheet with marking material, recording marks on the record sheet representing electrical signals, and exposing the record sheet to the action of light and heat simultaneously thereby to render the marking material inert and to smooth or iron the record sheet.

Other objects and advantages of the invention will become apparent and immediately suggest themselves to those skilled in the art when the following specification is read in connection with the accompanying drawings in which:

Fig. 1 is a diagrammatic showing of a recorder of electrical signals embodying the invention;

Fig. 2 is a fragmentary howing of a modified arrangement of the recorder of Fig. 1; and

Fig. 3 is similar to Fig. 1 and shows a further modification of the recorder in accordance with the invention.

Referring for the present to Fig. l of the drawings there is shown, by way of example, a recorder which is suitable for producing marks in accordance with facsimile signals. This recorder is generally of the character described in U. S. Patent No. 2,215,806 granted to the present inventor On September 24, 1940. By reason of the invention disclosed herein considerable improvement in the method of obtaining the final record and in the apparatus which embodies features for carrying out the improved method is presented over the general disclosure of the above noted Patent No. 2,215,806 and other patents showing prior art electrical recording arrangements. Although the description of the illustrative embodiment to be given hereinafter refers to recording electrical signals by means of a helical recorder, called, it will be understood that the electrodes for the-application of recording currents to the record sheet may take any desired form. For example, a stylus may be employed which traverses the sheet in a manner to produce complete scanning of the sheet as it is moved through the recording zone.

In the form shown, the recorder comprises a recording drum member l2, provided with a radially projecting helical electrode l I mounted on its periphery which cooperates with a second electrode in the form of a printer bar member I. This printer bar member is or may be carried by light pressure producing means, for example springs l8, one of which appears in Fig. 1. The springs it are secured on an insulating member I! mounted on any convenient stationary portion of the apparatus.

Reference character 23 designates a signal or facsimile receiver of any known type which is in communication with a signal input source 24. Signals suitable for recording are applied to the recording electrodes i4 and i6 from the receiver '22 over connections 26. One of the connections may be in communication with a brush 28 which bears on the drum shaft 29, or the frame of the apparatus (not shown) as well as one terminal or connection 28 from the receiver 23 may be grounded to complete the connection to the recording electrodes. It will be understood that the helix I4 is conductively connected to the drum shaft 29.

The record sheet or paper web 3|, which is threaded between the printer bar Ii and the helical electrode I4, is, in the illustrative example,

aesaeee' drawn through the recording zone by a pressure roller '32 which cooperates with a guide roller 33. One or both of these rollers may be driven by a motor 38 through a speed reducing mechanism such as a gear box 38. The rotatable drum H2 is also driven from the motor 35 through the gear box 38. The mechanical connections are indicated schematically by the dot-dash lines 39 and M. The motor 36 may be of the synchronous type connected to the alternating current service connection 44. Where the motor 36 is connected to the same synchronized system as the motor (not shown) which drives the transmitting system, it will not, in general, be necessary to provide separate synchronizing signals. Synchronizing and phasing signals may be generated and transmit ted as described in U. S. Patent 2,326,740 granted to Maurice. Artzt on August 17, 1943, when desirable or necessary.

Since the elements so far described are well known per se and generally of themselves do plied material or produced so as to therein or thereon,

mentioned transparent cylinder 52 to be exposed not form the particular basis of this invention,

they are illustrated herein more or less diagrammatically. Further details or the helical recorder with respect to the paper Ieeding means and other conventional features are to be -found in U. S. Reissue Patent Re. 20,152 granted to the present inventor on October 27, 1936. The recorder in this last named patent, however, relies on a transfer, of marking material to produce markings by vibrating the printer bar rather than on electrical or other processes which depend upon a direct application of electrical effects to the record sheet.- Other details of a facsimile recorder employing an eletroiytic process for producing marks are shown in U. S. Patent 2,391,765 granted to Maurice Artzt on December 25, 1945.

The recording web 3| is fed from a supply roll 45 and passes through a tank or tray 48 so as to be wetted by a liquid bath 49, the nature of which will be discussed more in detail hereinafter. The web 3| is guided throughthe liquid in the bath by suitable means such as idler rollers 5| and 52. The excess moisture is scraped oil on the edge 53 of the tank 48 as it passes from the guide roller 52 over a guide roller 58. The latter is located, with respect to the roller 52 and the edge 53, so that the web 3| is brought in contact with the edge 53. The placement of the roller 55 is not critical inasmuch as the web 3| is immersed in the bath 49 and its moisture content on leaving the bath will be fairly constant. Therefore, the roller 56 may remain fixed for a given and more or less predetermined tension in the web 3|.

The web 3| is guided by an idler roller 59 so that it passes through the recording zone in substantially tangential contact with the helix l4. In the arrangement of Fig. 1 there is shown a, web treating device indicated in its entirety by reference character 5| which comprises a trans- I parent cylinder 62 positioned to receive the web 3| as it comes from the drum I2 and over which it passes into peripheral contact with the drive roller 33 or other equivalent propelling device.

. The cylinder 62 may be formed of glass or a suitable heat resistant transparent plastic.

Briefly, at this point, it may be stated that the bath 49 conditions the web 3| for marking in the recording zone by providing it with a substance or substances which produce a color change under the influence of signals applied from the facsimile receiver 23 or other suitable signal source. The web 3|, which has been marked so as to exhibit an image. or in the epto the influence of strong light which destroys the susceptibility of the substance or substances applied in the bath 49 to any further color change.

The distance of travel or the web between the printer bar Hi and the transparent cylinder 62 permits the full development of a latent or partially latent image to a visible image in the event that the bath 49 provides a substance or substances which does not produce'a mark instantaneously upon application of the signal current on the printer electrodes. For example, a dye may be formed by the action of the signal currents but this dye may not always iorm instantaneously. The distance between the printer bar |6 and the transparent cylinder 62 should be properly selected to permit complete color reaction, and still fix the background soon enough to avoid an darkening. I

The transparent cylinder 62 contains a light source which may be in the form of a lamp '64 comprising a transparent cylinder 66 and a light emitting'filament or the like 88. The lamp 64 is backed by a reflector 69 so as to direct the light with full intensity upon the web 3| as it passes over the cylinder 62. The lamp 64 is preferably of the type which produces a considerable quantity of heat so that the web may be smoothed and dried.

The smoothing eflect on the web 3| is enhanced by a belt 19 of flexible material such as canvas or the like. This belt passes over guide rollers II to 13. The guide roller-12 is or may be driven so the belt 10 moves at the peripheral speed of the web 3|. A driving connection is indicated schematically at 14.

' The lamp 54 is connected to a suitable supply source indicated at 16 through an adjustable control such as a rheostat 11. The purpose of this rheostat is to provide for controlling the degree of heat obtained from the light source 59. In this connection it will be understood that a light source with suflicient brilliance is preferably provided even when the rheostat I1 is adjusted to provide a low'degree or heat. In general, ex-

.cessive brilliance of the lamp 64 will have substantially no effect on the markings 18 on the web 31. The device 6| may, if desired, contain an arc lamp or are lamps or any other suitable source or light which provides considerable heat in operation. If arc lighting is used in the device 5|, the preferred arrangement will be to employ several arc lamps so arranged that the light distribution is substantially uniform even when one or more of these lamps are cut oil. This will provide for controlling the amount of heat generated without impairing the background treatment of the record sheet 3 The bath 49 may contain, in solution or otherwise, two substances which will react together at the printing electrode l5 upon application of current to produce a marking material, for example, a dye. When dye formation is to be obtained electrolytically, the bath 49 may contain two components of an azo dye in solution. The bath is prepared so that these two components do not combine bymaking the solution slightly acid. By way of example, the bath 49 may be an aqueous solution of a diazonium salt or a. source of such salt. The other component may be an azo dye coupler. A suitable solution is disclosed and claimed in the copending applicasodium chloride in the bath 49. In general, electrolytes which are chemically inert with respect to the diazonium salt and the acid may be used.

Some degree of change in the moisture content of the web 3| occurs as it progresses toward the recording zone and the length of the travel of the web may be adjusted so that it arrives at the recording zone sufhciently wet to be conductive and to promote chemical reaction. If, for mechanical or other reasons, the tray 48 must be more or less remote from the recording zone, the web 31 may traverse a closed passage formed by baille plates (not shown) or the like. The machine is preferably arranged so that no light rangement for washing a sheet as well as exposwashed and exposed to light.

from the fixing unit can reach the dye solution or the treated paper before the printing point.

Formation of the diazonium compound, for example, and formation of the azo dye within a short time thereafter in the recording zone in the presence of electric signals produces marks on the web or sheet 31. As pointed out previously, if the formation of the dye does not occur immediately the time of travel and hence the length of the portion of the web between the recording zone and the cylinder 62 is of importance. Fig. 2 to be subsequently described provides means for setting this preferably prior to the beginning of a run or during a brief test run.

The diazonium salt remaining unused in the web is converted into a stable compound, for example, a phenol, so that no further dye formation can occur. A permanent white background for the marks thus is obtained. At the same time, the heat of the light source, as pointed out before, serves to iron the damp sheet to a smooth surface.

Referring to Fig. 2 of the drawings there is shown means for adjusting the length of -webwhich extends between the recorder and the light treating device. Inasmuch as the recording means and the light treating device may be the same as shown in Fig. l or their equivalents, the same reference characters will be used for like parts with the addition of the sumx "a." The recording drum 12a and the printer bar lBa are displaced as shown from the treating device ila. Two guide rollers 8| and 82 are rotatably supported in position so that they are approximately tangential to the web 31a as it extends from the recording zone to the treating device 6 la. A third roller 84 is rotatably supported and is movable so as to draw the web into a loop thereby providing for a greater length of web between the regions mentionedabove; The roller 84 may be supported by swingable arms 85 which are swingably mounted at or adjacent the axis of the roller 82. Clamping means are provided for maintaining the roller 84 in its selected position and may take the form of arcuate members (one shown) 88 each of which is provided with a slot 88. Clamping means such as a wing nut 9| may be threaded on to a stud I02 which is in turn secured to any stationary part of the apparatus. From what has been stated previously, it is believed that the purpose for and adjustment of the movable roller 84 will be understood.

Referring to Fig. 3 parts which are similar to those in Fig. 1 will have similar reference characters with the sufiix b."

The tank 48b contains a solution I86 whichis applied to the web 3Ib in the manner previously described. Excess moisture is scraped off by the edge 53b of the tank or its equivalent. The web Slb, after passing through the recording zone where it is acted on by the helical electrode b on the drum Rb and the printer bar lib, is passed through a tank I". Guide rollers I H and H2 within the tank insure-immersion of the web in a bath H4. guide roller 8 is provided, as shown, to maintain the web 8lb substantially tangential to the helical electrode b. The treating device ilb is or may be the same as the device 6| of Fig. 1 of the drawing, or the equivalents discussed in the foregoing.

After washing, the web 3| is exposed to light and heat over the transparent cylinder 8212. Drive rollers 82b and 33b serve to propel the sheet or web 3112 in a manner previously described. A belt 10b may be included if desired.

The bath H4 may be a water bath or itmay be a solution which promotes fixing of the background of the web 81b.

The belt I0 of Fig. 1 and the belt 10b of Fig. 3 may be utilized as the sole means of propelling the web through the apparatus. If this is done, the drive and pressure rolls 32 and 33, for example, of Fig. 1 may be eliminated. The cylinder 82 may be fixed or free running depending on the conditions of friction and paper tension in a given assembly. With the device so arranged, there is combined in one unit the function of web feed, light fixing and ironing.

Having now described the invention, what is claimed and desired to be secured by Letters Patcut is the following:

1. Facsimile recording apparatus comprising means for producing a record electrolytically which is visible on a record sheet, means for thereafter treating said record sheet with light from a light source to fix the color of the background of said sheet, said light source being of a nature to evolve heat, and means for utilizing the heat from said light source to dry and smooth the sheet. v

2. Facsimile recording apparatus comprising means for producing a record electrolytically which is visible on a record sheet, means for thereafter treating fsaid record sheet with. light from a light source to fix the color of the back ground of said sheet, said light source being of a nature to evolve heat, means for utilizing the heat from said light source to dry and smooth the sheet, and means for regulating the effective temperature of the light source while maintaining sufficient light for fixing the sheet.

3. Facsimile recording apparatus comprising means for producing a record electrolytically which is visible on a record sheet, means for applying a sensitizing liquid to the sheet, means for removing surplus liquid from the sheet, means for treating said record sheet with light following production of a record thereon, said light treating means being of a nature to evolve heat, and means utilizing the evolved heat to iron the record sheet.

4. Facsimile recording apparatus comprising means for producing a record electrolytically sesame which is visible on a record sheet, means for thereafter treating said record sheet with light UNITED STATES PATENTS from a light source to fix the color of the back= Number Name Date ground of said sheet, and means associated with 941,721 Moss Nov, 30, 1909 said treating means to propel said sheet through 5 7,109 Bhankweiler Dec. 31, 1949 the g q 2,311,849 McDonald Feb. 23, 19%

" CHARLES J. 1 01mm. ,3 ,765 Amt Dec. 25, 1945 REFERENCES @HTIEID) 

